Eclipse Content Assist Freezes

Greetings Eclipse Users,
I have been facing a problem with Eclipse's content assist. There was no particular time when it started. It just gradually got worse. When I go to type in a method name for an object, here is the sequence of events:
1) Type in object name
2) Type '.'
3) Content assist list pops up. No freeze yet.
4) Begin typing first few letters of method.
5) Only the first letter shows up. Eclipse freezes.
6) Processor usage jumps to 70%
7) 5-10 seconds later Eclipse window grays out, says Not Responding
8) ... ... ... 15-30 seconds later... ...
9) Eclipse unfreezes.
10) The next few letters show up.
11) The content-assist pop-up catches up, and shows the right suggestions.

I have come across many mentions of slightly similar problems and almost as many suggested solutions. None of them have worked so far. If you have seen this problem exactly, how did you solve it?

Here is a screenshot. This is what I see for 15-50 seconds. I still use content assist so disabling it is not currently an option. Note: Reinstalling eclipse did not solve the problem, it only decreased it.

Who is Participating?

I still don't know what the original cause was (or even if it is still in effect), but after many iterations on fresh installs, I found a particular combination of two actions that did the trick.

Part 1: Use only a JDK, not a JRE. Switch all Eclipse references to the JDK. Make sure to get them all. Start with: Preferences -> Java -> Installed JREs

Part 2: Download the official Java doc files (~50MB zipped) and keep it locally (instead of Eclipse hitting the URLs for content assist.)
Point Eclipse to the local copy: Preferences -> Java -> Installed JREs -> <the JDK> -> [Edit]
- For each "JRE System Library", choose the Javadoc location...
- Select the location of the local javadocs. Multiple ways to do this.

Restart Eclipse is the only thing that helps if it start freezing on me -- usually after having it up for 2-3 days, Content Assist will become highly inrespsnitive and Eclipse needs a restart. Occasionally that stops working in which case I would wipe Eclipse, unzip it clean and recreate all projects (which is a pain)

Does this happen every time? If so - how much memory do you have on the machine (that's a Java Editor after all)

Does it happen in every project? If just in one - recreate it

When you said you reinstalled Eclipse - do you just removed the old one and unzippied a new one and kept using the same projects or did you also recreate all projects from scratch? If the latter -- well... the problem still can be in one of the projects.